A new study suggests that omega-3, a fatty acid commonly found in fish oil, may have long-term neurodevelopmental effects that ultimately reduce antisocial and aggressive behavior in children.
The new study is a continuation of research begun by Adrian Raine of the University of Pennsylvania when he was a graduate student. That’s when he joined with other researchers to conduct a longitudinal study of children in the small island nation of Mauritius.
The researchers tracked the development of children who had participated in an enrichment program as three year-olds, as well as the development of children who did not participate. This enrichment program had additional cognitive stimulation, physical exercise, and nutritional enrichment.
At 11 years, participants in the enrichment program showed a marked improvement in brain function as measured by EEG, as compared to those who didn’t participate. At age 23, they showed a 34 percent reduction in criminal behavior.
Raine and his colleagues wanted to figure out the mechanisms behind this improvement. Other studies suggested the nutritional component was worth a closer look, he said.
“We saw children who had poor nutritional status at age three were more antisocial and aggressive at eight, 11 and 17,” Raine said. “That made us look back at the intervention and see what stood out about the nutritional component. Part of the enrichment was the children receiving an extra two and a half portions of fish a week.”
Other research has shown that omega-3 is critical to brain development and function.
“Omega-3 regulates neurotransmitters, enhances the life of a neuron, and increases dendritic branching, but our bodies do not produce it. We can only get it from the environment,” Raine said.
Research on the neuroanatomy of violent criminals suggested this might be a place to intervene, he said. Other researchers have shown that omega-3 supplementation increases the function of the dorsolateral prefrontal cortex, a region Raine found to have higher rates of damage or dysfunction in criminal offenders.
The new study featured a randomized controlled trial where 100 children, between the ages of eight and 16, received regular omega-3 supplements in the form of a juice drink for six months. Another 100 children received the same drink without the supplement.
The children and parents in both groups took a series of personality assessments and questionnaires at the start of the trial, according to the researchers.
After six months, the researchers administered a blood test to see if the children in the experimental group had higher levels of omega-3 than those in the controls. They also had both parents and children take the personality assessments.
Six months after that, the researchers had parents and children take the assessment again to see if there were any lasting effects from the supplements.
The assessments had parents rate their children on “externalizing” aggressive and antisocial behavior, such as getting into fights or lying, as well as “internalizing” behavior, such as depression, anxiety, and withdrawal. Children were also asked to rate themselves on these traits.
While the children’s self-reports remained flat for both groups, the average rate of antisocial and aggressive behavior as described by the parents dropped in both groups by the six-month point, according to the study’s findings.
Those rates returned to the baseline for the control group, but remained lowered in the experimental group, at the 12-month point, according to the findings.
“Compared to the baseline at zero months, both groups show improvement in both the externalizing and internalizing behavior problems after six months,” Raine said, explaining, “That’s the placebo effect.”
“But what was particularly interesting was what was happening at 12 months,” he continued. “The control group returned to the baseline while the omega-3 group continued to go down. In the end, we saw a 42 percent reduction in scores on externalizing behavior and 62 percent reduction in internalizing behavior.”
At both the six- and 12-month check-ins, parents also answered questionnaires about their own behavioral traits. Surprisingly, parents also showed an improvement in their antisocial and aggressive behavior.
This could be explained by the parents taking some of their child’s supplement, or simply because of a positive response to their child’s own behavioral improvement, according to the researchers.
The researchers caution that this is still preliminary work in uncovering the role nutrition plays in the link between brain development and antisocial behavior. The changes seen in the one-year period of the experiment may not last, and the results may not be generalizable outside the unique context of Mauritius, they say.
Beyond these caveats, however, there is reason to further examine omega-3’s role as a potential early intervention for antisocial behavior, the researchers say.
“As a protective factor for reducing behavior problems in children, nutrition is a promising option,” said Jianghong Liu, Ph.D., an associate professor in the Penn School of Nursing. “It is relatively inexpensive and can be easy to manage.”
According to the researchers, follow-up studies will include longer-term surveillance of children’s behavioral traits, as well as investigating why their self-reports did not match the parental reports.
The study was published in the Journal of Child Psychology and Psychiatry.
Source: University of Pennsylvania